The electronic control of devices such as door locks can be a great convenience and time save for a user. For instance, the advent of remote controlled and semi-automatic door locks on cars has been a popular success with consumers.
However, for entry doors in a building, the electrical operation of locks is accomplished with mechanisms that extend or retract the latch bolt of the door lock in and out of the strike plate mounted on a doorjamb. One drawback of these devices is that it takes considerable electrical energy to move a latch bolt, particularly if frictional forces are present, such as wind forces on the door and bolt. Another drawback is that they require an expensive lock mechanism usually requiring a complicated installation. Despite these disadvantage, these devices are used in mortise locks in commercial and institutional environments, such as hotels.
Some entry doors include entry security systems. Such security systems sometimes include a sensor mounted on the door which conveys the open or closed status of the door. A central control is used to activate and deactivate the sensor. A provision is usually made to warn the occupant in the event that the door has been left open which must be corrected before activating the system. There is no provision, however to warn the occupant that a door may be unlocked. To determine the locked status, the occupant must visit and check each door. An unlocked door could lead to an intrusion or a costly and upsetting false alarm. Furthermore, present systems inconveniently require that when an occupant arrives at the premise they must use a key to gain entry and then operate an alarm control keypad to de-activate the alarm.
Accordingly, there is a need for a low-cost, easily installable door entry system which provides electronic access and control, and which provides for more full-featured security.